U.S. patent document 2003/0221455A1 discloses a system for flame-deposition of carbon onto the glass-contacting surfaces of a glassware forming mold. A burner includes a nozzle having separate fuel and oxidant gas passages that terminate in respective pluralities of outlet ports from the nozzle. The pluralities of outlet ports preferably form an annular composite array in which the fuel and oxidant outlet ports alternate with each other. The oxidant outlet ports preferably comprise slots having long dimensions radial to the annular array. The fuel outlet ports preferably are circular. A pair of spark electrodes, including an ignition electrode and a ground electrode, are spaced from each other and disposed within the gas stream emerging from the burner. The electrodes are energized to ignite the carbon-containing gas mixture and form a flame that precipitates electrically conductive carbon particles onto the glass-contacting surfaces of the mold.
Immersion of the electrodes in the flame path makes the electrodes susceptible to carbon buildup. Furthermore, the electrodes can deflect or alter the flame pattern, particularly as carbon builds up on the electrodes, resulting in less than optimum carbon deposition on the mold surfaces. U.S. application Ser. No. 11/190,366 filed Jul. 27, 2005 discloses a burner in which one of the electrodes is carried by the burner nozzle so as to be surrounded by the ignited flame while the other electrode is positioned outside of the flame. It is a general object of the present disclosure to provide a glassware mold lubrication system that reduces or eliminates carbon deposition on the spark electrodes, in which the electrodes do not affect the flame pattern of the ignited carbon-containing gas, and in which the spark electrodes (both ignition and ground electrodes) are carried as an assembly with the burner nozzle.
The present disclosure embodies a number of aspects that can be implemented separately from or in combination with each other.
A burner for depositing carbon soot on a glassware mold, in accordance with one aspect of the present disclosure, includes a burner nozzle having an annular array of individual gas outlet ports, a fuel passage within the nozzle connected to a first plurality of the outlet ports and an oxidant passage in the nozzle connected to a second plurality of the outlet ports. The first plurality of outlet ports individually alternate with the second plurality of outlet ports around the annular array such that the array presents alternate fuel and oxidant outlet ports around the array. An ignition electrode is disposed on the burner nozzle within the annular array of outlet ports for igniting fuel and oxidant emerging from the outlet ports. The ignition electrode preferably is in the form of an elongated ignition electrode rod telescopically surrounded by an insulator and centered on the burner nozzle within the annular array of outlet ports, and a ground electrode telescopically surrounding the insulator. The ground electrode preferably is part of the burner nozzle and is electrically connected to a burner mounting block on which the burner nozzle is mounted.